Hi juveman.
You are welcome!
You are correct, I placed a slight caution for this mattress as this will not be as durable for higher weight ranges.
I would first take into account that all the layers in a mattress work together and will affect the overall feel and performance of the mattress. Because you are the only one that can feel what you feel on a mattress as there are too many unknowns, variables, and personal preferences involved that are unique only to you, in the end, it would be left to you to decide which feel you like best. Both innersprings and a poly foam core can be used as a support layer and each has very “different” characteristics, but besides the more obvious ones the most important differences are the ones you can feel and that you personally prefer. Both of them come in softer or firmer versions and in many different designs so an innerspring could be firmer than a poly core and more supportive or the other way around depending on the specifics of the components you are comparing.
Generally speaking for higher BMI ranges I usually recommend spring or latex support layers but I would rely on the advice of Nestbedding themselves as they are much more familiar with their own mattress designs, the type of springs they have and the materials in the componentry than anyone else (including me) and they can use the information you provide them about your body type and sleeping positions, your preferences, your history on different mattresses, along the results of your local testing to make suggestions based on the “averages” of other customers that are higher BMI.
There is more about the 4 main types of innersprings in this article and in post #10 here and if you decide to look at a latex core then there is more detailed information about innersprings vs latex support cores in [url=https://forum.mattressunderground.com/t/all-latex-versus-latex-top-on-inner-spring-mattresspost #2 here [/url]
Phoenix